Astro-Harness

The Astro-Harness is a piece of Legendary (5-star) gear that can be evolved from the Epic (4-star) gear, Astro Force, which can be obtained by ranking in the top 5% of certain Online Battle seasons. The ultimate tanking gear, Astro-Harness can negate astonishing amounts of damage with good timing without having to rely on luck, but has weak offense and lacks persistent effects after its many shields are exhausted.

The "Power Shield" works like a secondary health bar that overlays the main health bar and will activate upon a hit that would have knocked out the user, similar to resurrection. The main health bar and Power Shield are both separate and thus, the main health will not be affected until the shield is used up while healing restores health but not the shield. The shield is not affected by life drain as it does not count as actual health. As the effect is additive, any remaining damage that is not absorbed will carry over to the main health bar. A single large hit can instantly deplete the power shield and its animation will not be displayed despite having been triggered. Tagging out will remove the power shield.

The Power shield is similar to Killer Croc/Arkham's Armor, but cannot be regenerated after being triggered. Armor is also not removed on tag. If both are active, power shield will be depleted first.

Tag-in stuns (e.g. Cloak of Destiny) and Green Lantern/Jessica Cruz Rebirth's stasis passive will ignore the Power Shield and deal damage to health directly (the 1 or 2 damage dealt by the stun, not any follow-up attacks). If the target already had 1 health left when power shield is triggered, the stun can immediately knock them out.

Effects that deal damage according to a percentage of maximum health (e.g. The Ibistick's burn) will affect the shield according to max health as normal. Effects that deal % current health damage (e.g. Batgirl/Cassandra Cain's passive) will not count the shield in calculations; if the user has exactly 1 health left, no damage will be dealt, even though they have a significant amount of power shield. Batman/Blackest Night's passive will also only take health into account. At 1 health on his target, his passive would always be at maximum damage regardless of power shield.

There is a bug that sometimes causes every hit to be displayed twice after power shield is triggered.

The invulnerability is activated at three health thresholds (similar to Green Lantern/John Stewart's Passive) and if active, can be used to completely ignore all damage, including Super Moves, for 3-5 seconds. Since the invulnerability can be triggered at full health which is at the start of the match, it can be used against characters with starting bars of power and even 3 full bars such as Green Lantern/Red Lantern Hal Jordan and Batman/Arkham Knight (when equipped with Ra's Al Ghul's Scimitar or paired up with Batgirl/Prime) as both can use a super move at the start of the match. It is recommended to not put Astro-Harness on your first character to avoid wasting it if there is no immediate threat at the beginning of the match, and instead tag in your Astro-Harness character when the threat arises. It can also stack with Green Lantern/John Stewart or teammates paired with him to give one of them four layers of invulnerability. The same goes for Superman/Injustice 2 as the invulnerability will not affect his passive until it wears off.

Additionally, despite its description, the invulnerability is reset after each match even after losing some health provided you don't fall below the next threshold (e.g. you can start a match with 80% health, and the 100% health invulnerability would be active). Thus, if equipped on your starter, it is uniquely useful as an invulnerability tool in Survivor mode completely countering Batman/Arkham Origins, Batman/Arkham Knight, Batgirl/Prime, and Green Lantern/Red Lantern Hal Jordan no matter which round you are on.

Both the invulnerability and Power Shield trigger separately and independently, meaning it is possible to trigger Power Shield before the second and third phases of invulnerability, if overkill damage is dealt.

Like other DOT gears before the nerf, the electrical DOT is applied after the special, meaning that if equipped on Harley Quinn, she can apply it on her SP2 regardless of the choices she picked. Aquaman/Prime is a strange case: it appears that the electric DOT is only applied when one of Aquaman's teammates tag in (regardless of when and whether the hero was knocked out), dealing 2% of Aquaman's damage over 5 seconds. But if the hero attacked the opponent, the damage is scaled to the damage dealt, around 0.65% of the damage dealt. Either way, the damage is negligible and mostly serves as a curiosity.